Some conventional ribbon cassettes include a driver gear which is driven by the printer drive shaft and an idler gear disposed in spaced adjacent relation so that a ribbon may pass therebetween where it is squeezed (pinched) between the gears and advanced into a storage cavity of the cassette. Normally, such structure requires a spring to bias the gears together for engagement with the ribbon. Additionally, a ribbon removal device or "stripper" is required so that the ribbon will not wind around the driver or the idler gear.
The ribbon removal device (stripper) typically is mounted in the central region of the driver and idler gears and may be comprised of a plurality of fingers extending between superimposed toothed layers which make up the gears. As many as four or five fingers may be required depending on the size of the gears in order to provide the necessary "stripping" action. Additionally, since the fingers are mounted on a separate support and extend inwardly between the toothed layers which extend from a common central post, each finger must have an arcuate cut-out or slot at the ends thereof which fit partially around the central post.
To manufacture such an apparatus, a complicated cam-operated sold base is required, and due to the case and required space for the cams, the cost per square inch to produce the mold is very high. The required cam-loaded mold adds a minimum of 20% to 35% to the injection mold cycle.
Furthermore, the use of strippers, which are made up of a multiplicity of inwardly extending fingers, requires an undue number of parts, each of which adds to the cost of manufacture. Additionally, the time that it takes to assemble the devices into the ribbon casing is excessive.
Accordingly, it is an object of the present invention to provide a simple, inexpensive device for preventing ribbon from winding around or otherwise binding to a gear or gears which are disposed for engaged relation with the ribbon for driving the ribbon in a predetermined path.
It is a further object of the present invention to provide such a device which will both serve to rotatably support the gear in the casing while also serving as a stripper to prevent the ribbon from winding around or otherwise binding to the gear or gears.
It is yet another object of the present invention to provide such a ribbon cassette with a ribbon storage compartment having a storage separator to separate the ribbon in orderly storage from a compartment entrance section of the cassette.
Another object of the present invention is to provide such storage separator with a ribbon separator which coacts with the storage separator to direct the ribbon into the storage compartment for efficient, orderly storage therein.
It is yet another object of the present invention to provide such a device which is simple in structure, inexpensive to manufacture, and requires no time to assemble in the casing since it is made a part of the casing in the molding process.